Figure 4

Identification of residues required for Vpr oligomerization. (A) Schematic figure depicting Vpr mutants selected for analysis. Substitution residue(s) are marked at appropriate place and a Δ represent deletion of a residue. NL43 sequence was used as wild type clone. (B) Expression of Vpr mutants was assessed in HEK293T cells by transient transfection. HEK293T cells were transfected with Vpr mutant expression plasmids or vector control plasmid and assessed for expression by western blot using antibodies against HA epitope to detect fusion protein. Tubulin was used as a loading control. (C) Visualization of oligomerization and subcellular distribution of Vpr mutant molecules was assessed by BiFC. HeLa cells were transfected with VC and VN combinations of Vpr mutants as described. Thirty-six hours posttransfection cells were stained for Vpr (shown in Red) and DAPI (blue) and imaged at 60× magnification. Figure represents one of five independent experiments (n = 5) with similar results.